Have you seen Marina Abramovic"s "The Artist is Present" documentary? It is about her performance in MOMA when she was siting still for three month looking into faces of the strangers. So impressive, about devotion, madness, sacrifice, stubbornness, talent of the true artist. Already several years I can not forget it. Here is the link to Youtube trailers. If you want full movie, I can probably find the link.
This guy was one of the many who sat in front of Marina.